Fluid-operated percussion-tool.



i To all'wkoht it concern 1 UNITED STATES rA'rE tr OFFICE.

CHARLES H.- HAESELER, or PHILADELPHrA, PENNSYLVANIA.

FLUID-OBERATED PEaoUssxoN'T'rooL.

Specification of Letters Patent;

Application filed necemb r rxmn. Serial No. 664.929;

Be it knofvn that- I, CHARLES H. HQESELER,

Y a citizen of t e United States, residing in the city of Philadelphia, county of Philadelphia, and State of Pennsylvania;

have

invented certain Improvements in Fluid- I Operated Percussion-Tools, of which the provement on the fluid operated percussion tools, particularly rock '-drill"s-, described in my. Letters" Patent of the United States numbered 994,743.

In the operation of rock drills, ivhen \i"orking through soft and plasticstrata, the. retraction of the drill'rod is resisted by the friction and a'dhesion'of the material. This resistance renders it at times unnecessary and undesirable to impose the check on the reverse stroke of theoperating piston which is effected by the-entrapped elastic fluid, as provided in my said patent, and i'sa desideratum in cutting through solid "materiah It is the primary object'of-thisinvention to improve the-apparatus of my'said patent by {providing the same with convenient ,means for regulatingthe fluid entrapped to vcushion the-return movement of the operating' piston, asalsoto wholly eliminate, the cushion and the resistance-otherwise op in illustrationthereofs j g r I In the drawings, Figure is a' sect-ional side elevation of a rock drill embodying my invention; Fig.2 is an enlargedsectional view transverse .to that of Fig. 1, illustrating the valve mechanism embodied in my. improvements; and Fig. 3 is a perspective view of the valve shown in Fig. 2.

The drill, as illustrated in the drawings,

'comprises the cylinder 1 having the pas which communicate with its the percussive piston 4 reciproca-ted in the cylinder-1 by motive fluid acting through-the passages 2 andv 3, the valve 5 which is reciprocated to control the passages 2 and 3 by the rocker 6 oscillated b 7 which engages the rifled wall of the cham her 8, has the piston 9 thereon whlch acts in the chamber, and contains the nassage 1O controlled by the valve 11 and the ports )1 passages- 12 controlled bv the piston 4 sages 2 and 3 oluble. and longitudinally movable being adapted for closing .the pass the application of a'wrencheor key.

resistance to the. withdrawal or retraction of the cutting mechanism, so as to render retraction. the stem 22 is turned. so that the piston 4, and. the-rifled rotator barfor communicating motive=fiuid from" the rear end of the cylinder -1 to-tl1e cha-mh,er 8 in front of the piston .9 :and' trapping '.,it in such chamber, asp described in ply-"5s: l patent; 1 In my present invention, in-its preferred form, thebar 7 is provided=wit-h"' theavial passage 13 which'int-ersect-s the ports'liia provides a bearing for a .rcd, alve i bearing to control. said ports, I said i s A cam 1'5, fixed on the valve,'is re 'oluhle-in the cylindrical recess 16, inthe-Tear;end of the bar Tan'dengages. the cam' 18 *foriuediii the head 19 of the cylinder 1. A spring.20,

disposed on the rod 14, is-seatedin the rej-' cess 21 of the bar 7' and bears against the cam 15 to hold it in engagement with gthe cam 18. A stem22, fixed to the cam 15,.e 'r; tends through and is revoluble in the. cylin v der head 19 and its yoke bars 23' and 24',

the stem having a head 25 and a hole 26' for.

In the normal operation of the drillf'in cutting through solid material, the 'valve 'H' is held in the position shoWn'inFig'fiZ, ino- Y tive fluid admitted-to therear endof the cylinder 1 to e fl'ectthe-forwa-rdstroke, of 35 the piston 4fiows through the passages 12- and .10 to the chamber .8 and on the backward; stroke vofthe piston the fluid-in this chamber is trapped by the automatic closure of the check valve 11, the entrapped fluidso "providing an elastic cushion imposing'lthe desired check on such backward movement.-

I But when the character of the material through which the drill is acting i-mpo sesthe air cushion unnecessary for the purpose of checking such retraction and undesirable because of the force opposed thereby to such the cam 15 shall be moved inwardly by the cam 18, and the valve 14 is moved inwardly so as to cut ofl' communication between the cylinder 1 and the passage 10, whereby the air cushion and its resistance to the retractile stroke are eliminated.

i Having described my invention. I claim: 1. In a fluid operated percussive tool. the combination with a cylinder and a percussive piston therein, of means for applying elastic motive fluid against a given area of the piston to move it in one direction. means i for entrapping motivefluid andfor compressing'itagainst a relatively smaller area during the movement of said piston in said j the piston to IIIOVG'it' ID direction, and means for rendering said last i-named means inoperative and.- eliminating the resistance due to the entrapping-of-md 2. In a fluid operated percus ivetool, the

combination with a cylinder anda percussive piston therein" means. for; applying inst a given area of elastic motive fluid a for entrapping motive fluid and for compressing it against. a relativelysmaller area. during the movementofsaid. piston insaid:

direction, and mechanism for controlling the entr'apping of said motive fluid and re ulat-- ing the resistance to said movementue tothe compression thereof. I I

3. In a fluid operated percussive tool, the

combination of a cylinder, a percussion pis'-.. ton movable" therein, an a ixiliary'xcylinder,

an. auxiliary piston acting in said auxiliary cylinder, means whereby motive fluid is communicated from said cylinder first named to and entrapped in said auxiliary cylinder,- and means for cutting off communication from said first named cylinder to said auxiliary cylinder.

4. In a fluid operated percussive tool, the. combination of a c linder 'a percussion pis-' --t-on movable therein, vap "auxiliary cylinder Unsaid piston, an auxiliary-piston in'said auxiliary cylinder,=a passage whereby said cylinders communicat a --check1 valve for preventing the return of motive fluid. flowing from said cylinder first named through said passage to said auxiliary cylinder, and a :valve' for preventing the flowof motive fluid from said first cylinder through said passage to said auxiliary cylinder.

5. In'a fluid operated percussive tool, the

combination ofa cylinder, a percussion. pis-.

ton mo vable'therein, 'a rod engaged to said cylinder, an auxiliary piston on said rod, an auxiliary cylinder in said percussion p sand a valve .for preventing the normal adone direction, means ton in which said auxiliary piston acts, a passage forgadmitting fluid from said cylinder first named to said auxiliary cylinder mission of motive fluid to said auxiliary cylinderf" 6. In a fluid (operated percussive tool, the

combination of a cylinder, at percussion pis- 'to'n =movable therein, a chamber in said pistan, a rod provided with a ,piston in said chamber, a passage through said rodwhereby motive fluid is communicated from said cylinder to said chamber, and avalvecomprising a rod '-movable in said rod first named whereby said passage can be regu lated. I 7. In a fluid operated percussive tool, 'the combination of a cylinder, a percussion piston movable therein, a chamberjm-sa1d-p1ston, a-rod providedwith a piston in said chamber, a passage through-said rod and the piston thereon whereby fluid is communicated from said cylinder to said chamber, a check valve forfentrapping fluid in said chamber, and a valve comprising a rod movable in said rod first named whereby valve mechanism comprising a revoluble and longitudinally movable rod in combination with means whereby said rod'is moved 1on gitudinally by turning it. 7

In witness whereof I have hereunto set my name. this 9th day of December, l9l1, in

the presence of the subscribing witnesses.

CHARLES H. 'HAE ELER. .NVit-nesses:

J08) G. DENNY, Jr., CHARLES N. BUTLER. 

